This proposal seeks a five-year continuation of Monitoring the Future (MTF), an ongoing epidemiological and etiological research and reporting project begun in 1975. As well as being a basic research study, MTF has become the nation's most reliable source of information on trends in drug use among American adolescents, college students, and young adults. Annual, nationally representative sample surveys will be conducted of (a) eighth, tenth, and twelfth graders (16,000 in about 140 schools per year per grade), (b) panels of high school graduates aged 19-30, 35, 40 and 45 (by mail), and (c) panels drawn from the eighth grade classes of 1991-93 graduates (by mail). These data collection procedures (in-school and by mail) are highly cost efficient. [unreadable] [unreadable] The study's cohort-sequential design permits the measurement and differentiation of three types of changes--age (developmental), period (historical) and cohort. Each type has different kinds of determinants, and all three types have occurred for most drugs. Factors that may explain historical trends and cohort differences will be monitored. MTF has the further objectives of documenting the natural history of drug use and related attitudes through middle adulthood; determining what transitions in social roles and social environments contribute to them; and determining what features of those roles and environments are most influential. The study will examine the importance of many other hypothesized psychological, behavioral, and social determinants of drug use (including attitudes and beliefs about drugs, counter-advertising, role-modeling, and access limitations), as well as a range of potential consequences of drug use (including physical health, psychological well-being, status attainment, and role performance). The investigators will continue to facilitate use of MTF data by others for a hose of research purposes, including policy evaluation. [unreadable] [unreadable] The study's extensive measurement covers (a) initiation, use, and cessation for a great many licit and illicit drugs, (b) attitudes and beliefs about these drugs, as well as perceived availability, peer norms, and norms among role model groups, (c) other behaviors and individual characteristics (delinquency, school performance, plans and aspirations, etc.), and (d) aspects of key social environments (home, work, school and social role statuses, experiences, and transitions (marriage, pregnancy, parenthood, divorce). Study results will continue to have major implications for understanding and preventing drug use and abuse from adolescence through middle adulthood.